Diagnostic testing for mucolipidosis type IV. Carrier screening for mucolipidosis type IV.
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: Early onset of severe psychomotor delay, progressive visual impairment from corneal clouding and retinal degeneration. 15 percent of affected will have progressive neurological degeneration. Affected persons may learn to say a few words or walk independently.
Incidence: 1 in 63,000 Ashkenazi Jewish individuals; unknown in other ethnicities.
Inheritance: Autosomal recessive.
Cause: PathogenicMCOLN1 gene mutations.
Mutations Tested: g.511_6493del and c.406-2A>G.
Clinical Sensitivity: 95 percent in Ashkenazi Jewish individuals, unknown in other ethnicities.
Methodology: Multiplex polymerase chain reaction and Detection Primer Extension.
Analytical Sensitivity and Specificity: Greater than 99 percent.
Limitations: Mutations other than those tested will not be detected. Diagnostic errors can occur due to rare sequence variations.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|0051450||Mucolipidosis IV (MCOLN1) 2 Mut, Allele1||34658-5|
|0051451||Mucolipidosis IV (MCOLN1) 2 Mut, Allele2||34658-5|
|0051452||Mucolipidosis IV (MCOLN1) 2 Mut, InterpM||46965-0|
|2001329||Mucolipidosis IV (MCOLN1 2 Mut, Spec||31208-2|